Jens Böhmer: Blood test replaces heart biopsy for transplant patients
For patients with severe heart failure, a heart transplant may be the last resort. One significant complication is the body rejecting the new heart. Jens Böhmer’s research shows that rejection can be detected with a simple blood test. This new method reduces the need for time-consuming and painful heart biopsies.
Dissertation defense: 13 December 2024 (click for details)
Doctoral thesis: A new biomarker for the non-invasive diagnosis of rejection after transplantation
Research area: Pediatrics
Sahlgrenska Academy, The Institute of Clinical Sciences
The current standard involves regularly taking small tissue samples (biopsies) from the transplanted heart. This is typically done 10 to 12 times in the first year to monitor for rejection, a life-threatening complication.
“Biopsy is an expensive procedure and very unpleasant for the patient. Children must undergo anesthesia for this. It is also usually done at the transplant center, which means a lot of travel for the person who has received a new heart,” says Jens Böhmer, a pediatric cardiologist who, after nearly 15 years at Sahlgrenska University Hospital, now works at a children’s hospital in Frankfurt, Germany, while pursuing his doctoral studies at the University of Gothenburg.
Samples from across Sweden and Iceland
In his thesis, Jens Böhmer investigated small DNA fragments from the donor heart present in the patient’s blood and how they can be used to detect rejection. The results are so promising that the new method will be implemented for future patients.
How does the new technique work?
“We use a new PCR technique called droplet digital PCR, a highly sensitive PCR method, which had not been used at Sahlgrenska before. We observed that DNA levels were very low under normal circumstances but increased during rejection. We studied this in about 100 patients, including adults from half of Sweden and children from the entire country,” explains Jens Böhmer.
He adds, “This means we can rule out rejection with a simple blood test. The collection tubes we use stabilize the DNA in the sample, so they can be sent at room temperature. We have analyzed samples from across Sweden and even Iceland, without any differences in quality. This enables remote monitoring, as a blood sample from the patient’s local clinic is enough.”
“Saves a lot of money and suffering”
What has been enjoyable and what has been challenging about the doctoral project?
“This is a very special patient group, incredibly vulnerable, and they have truly been given a second chance at life. They deserve all our efforts. Establishing a new PCR method has been exciting. During the pandemic, PCR became something most people are familiar with.”
The study was unusually large for a doctoral project.
“We have worked on method development and included a lot of patients. But we are a fantastic team, and that has made it all possible. The absolute highlight is knowing that our method will be used for future patients. It can save a lot of money and suffering.”
Text: Jakob Lundberg
